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11.
12.
Gao X  Mohsin SK  Gatalica Z  Fu G  Sharma P  Nawaz Z 《Endocrinology》2005,146(4):1707-1712
The E6-associated protein (E6-AP) is a dual function protein. It acts as an E3 ubiquitin-protein ligase as well as a steroid hormone receptor coactivator. Considering the influence of steroid hormone receptors and their coactivators in the normal development and tumorigenesis of reproductive organs of both genders, we examined the roles of E6-AP in the tumorigenesis of breast and prostate tissues. We demonstrated that the expression of E6-AP protein is decreased in human invasive breast and prostate carcinomas compared with their adjacent normal tissues, and this down-regulation of E6-AP is accompanied by the up-regulation of estrogen receptor (ER)-alpha in breast and androgen receptor (AR) in prostate carcinomas. Furthermore, our in vivo data from E6-AP-knockout animals indicated that the expression levels of ERalpha and AR are increased in E6-AP-null mammary and prostate glands, respectively, when compared with that of normal control animals, suggesting that E6-AP modulates the protein levels of ERalpha in breast and AR in prostate glands.  相似文献   
13.
Over a year into the COVID-19 pandemic, there is growing evidence that SARS-CoV-2 infections among dogs are more common than previously thought. In this study, the prevalence of SARS-CoV-2 antibodies was investigated in two dog populations. The first group was comprised of 1069 dogs admitted to the Veterinary Teaching Hospital for any given reason. The second group included dogs that shared households with confirmed COVID-19 cases in humans. This study group numbered 78 dogs. In COVID-19 infected households, 43.9% tested ELISA positive, and neutralising antibodies were detected in 25.64% of dogs. Those data are comparable with the secondary attack rate in the human population. With 14.69% of dogs in the general population testing ELISA positive, there was a surge of SARS-CoV-2 infections within the dog population amid the second wave of the pandemic. Noticeably seroprevalence of SARS-CoV-2 in the dog and the human population did not differ at the end of the study period. Male sex, breed and age were identified as significant risk factors. This study gives strong evidence that while acute dog infections are mostly asymptomatic, they can pose a significant risk to dog health. Due to the retrospective nature of this study, samples for viral isolation and PCR were unavailable. Still, seropositive dogs had a 1.97 times greater risk for developing central nervous symptoms.  相似文献   
14.

Aim

To describe and compare mortality and population changes in the Roma and non-Roma population in Serbia in 2002 and 2005.

Methods

The number of cases of death were obtained from the 2002 and 2005 Mortality Database and population data from the Population Census 2002. Standardized sex specific rates of non-traumatic and traumatic mortality in 2002 and 2005 were calculated in relation to the European standard population. We presented population pyramid and aging index for both populations in 2002 and compared sex specific standardized traumatic and non-traumatic mortality rates and the average age of death for 2002 and 2005. The causes of death were coded according to the 10th revision of the International Classification of Diseases (ICD-10) groups, and the proportional mortalities in the year 2002 and 2005 were compared between the Roma and non-Roma population using χ2 test.

Results

Standardized mortality rates were higher in the Roma than in the general population. Non-traumatic mortality rate in Roma men in 2002 was 18.2 per 1000 and in slightly decreased to 18.0 per 1000 in 2005; it was significantly higher than in non-Roma men in both years (11.9 per 1000 in 2002 and 12.5 per 1000 in 2005; P<0.001). Standardized non-traumatic mortality rate in Roma women decreased significantly from 16.78 per 1000 in 2002 to 14.89 per 1000 in 2005 (P=0.014), but it was still significantly higher than in non-Roma women (8.46 per 1000 in 2002 and 8.84 per 1000 in 2005; P<0.001). Morbidity structure indicated that the most common causes of death in the Roma population were cardiovascular diseases, neoplasms, and respiratory system diseases. In relation to the general population respiratory system diseases were denoted as main causes of deaths in significantly higher percent (6% vs 3% in 2002 and 7% vs 4% in 2005; P<0.001) and cardiovascular diseases in significantly lower percent (44%:55% in 2002 and 46%:57%; P<0.001).

Conclusions

Our data show that mortality rates in the Roma population are significantly higher than in the general population, and morbidity structure of the most common causes of death significantly different from that of general population.According to the most recent population census in the Serbia from 2002, 108 193 or 1.44% residents declared themselves as Romani. The Roma population is among the most imperiled and potentially most vulnerable groups. Living Standards Measurement Survey (LSMS) conducted in Serbia in 2002-2003 indicated significant differences in living conditions between the Roma and non-Roma population (1). The prevalence of poverty, defined as an average total consumption below the poverty line of 57 euros per month/consumption unit, in the Roma population was as high as 64.4%, which is 6.1 times more frequent than in the general population (10.5%) (1). Extremely low level of education and very high level of unemployment characterize the social status of the Romani people. Almost two thirds (62%) of the Roma older than 15 years did not finish primary school, as opposed to 19% of the general population (1). The unemployment rate is also high, reaching 45%, while in the rest of the Serbian population it amounts to 9% (1). Such findings are not unexpected since these characteristics are highly associated with poverty (1).Although the range of vaccination coverage in Serbian general population is 98%-100%, many Roma children are not included in vaccination programs (2). Twenty nine percent of Roma children aged 18-29 months do not even have vaccination cards. Data regarding the education of Roma children are also discouraging: 62% of them attended pre-school programs one year prior to the first grade, as opposed to 89% children in the general population. Also, the vast majority (98%) of children of primary school age in general population attends school, while the attendance rate among Roma children is significantly lower (74%). The difference between the proportions of Roma children and children in general population who attend secondary schools is even more drastic (only 10% vs 85%).During the last decade, several studies dealing with diverse problems of the Roma population have been conducted in South-Eastern Europe (3-10). Compared with the general populations in Eastern and Central Europe, life expectancy of the Roma population is 10-year shorter because of poor living conditions and poverty (11). A study conducted in the Czechoslovakia in 1989 compared census data and pointed out that life expectancy of the Roma men and women were 12.1 and 14.4 years, respectively, shorter than in the general population (12).The aim of this study was to describe and compare mortality and population changes in the Roma and non-Roma population in Serbia in 2002 and 2005. We present population pyramid and aging index for both populations for the year 2002 and compared sex specific standardized traumatic and non-traumatic mortality rates and the average age of death for 2002 and 2005.  相似文献   
15.
A second pregnancy of young, nonconsanguineous parents of Macedonian ethnic origin was examined by ultrasound. Polyhydramnios and hydrops fetalis were found as well as severe short limb, short stature, and cystic hygroma of the neck. An artificial abortion was performed at the age of 23 weeks. The radiological features included moth‐eaten severely shortened long bones and ectopic calcifications of long bones, vertebral column, ribs, pelvis, larynx, trachea. In addition, the fetus had large head with depressed nasal bridge, severe platyspondyly, and short barrel‐shaped trunk. Light microscopy demonstrated lack of chondrocyte columns and disorganization of the cartilaginous architecture. This is the seventh reported case of this rare form of lethal skeletal dysplasia. © 2002 Wiley‐Liss, Inc.  相似文献   
16.
Minocycline is a useful adjuvant therapy for pemphigus   总被引:1,自引:0,他引:1  
Pemphigus is an autoimmune blistering disease with high mortality if untreated. The cases of 10 patients who had minocycline 100 mg daily added as adjuvant therapy are reported. Prior to the use of minocycline, all patients had active disease, nine were on prednisolone (10–40 mg) and five were on azathioprine (100–200 mg). The response was assessed on clinical improvement and reduction of immunosuppressive (IS) drugs. It was graded into four categories: major, minor, equivocal and no significant response. A major response was seen in four patients, minor in two, equivocal in one and no improvement in three patients. The prednisolone dose in the six responders was reduced to 0–6 mg (0 mg in three patients), with an average decrease of 21 mg. The average time to respond was 8 months. Of the six responders, three were on azathioprine, which was ceased in two patients and reduced by two-thirds in the other patient. No patient ceased minocycline because of side effects. In conclusion, minocycline 100 mg daily is a simple, safe and well tolerated treatment that should be tried in patients with pemphigus to reduce disease activity and/or the dose of potent IS agents.  相似文献   
17.
This paper presents four new temperature readout approaches to luminescence nanothermometry in spectral regions of biological transparency demonstrated on Yb3+/Er3+-doped yttrium aluminum garnet nanoparticles. Under the 10 638 cm−1 excitation, down-shifting near infrared emissions (>10 000 cm−1) are identified as those originating from Yb3+ ions'' 2F5/22F7/2 (∼9709 cm−1) and Er3+ ions'' 4I13/24I15/2 (∼6494 cm−1) electronic transitions and used for 4 conceptually different luminescence thermometry approaches. Observed variations in luminescence parameters with temperature offered an exceptional base for studying multiparametric temperature readouts. These include the temperature-dependence of: (i) intensity ratio between emissions from Stark components of Er3+ 4I13/2 level; (ii) intensity ratio between emissions of Yb3+ (2F5/22F7/2 transition) and Er3+ (4I13/24I15/2 transition); (iii) band shift and bandwidth and (iv) lifetime of the Yb3+ emission (2F5/22F7/2 transition) with maximal sensitivities of 1% K−1, 0.8% K−1, 0.09 cm−1 K−1, 0.46% K−1 and 0.86% K−1, respectively. The multimodal temperature readout provided by this material enables its application in different luminescence thermometry setups as well as improved the reliability of the temperature sensing by the cross-validation between measurements.

Four completely new NIR luminescence temperature readouts in the second and third biological windows are demonstrated with YAG:Er3+, Yb3+ nanoparticles.  相似文献   
18.
Acetylcholine-binding proteins (AChBPs) from mollusks are suitable structural and functional surrogates of the nicotinic acetylcholine receptors when combined with transmembrane spans of the nicotinic receptor. These proteins assemble as a pentamer with identical ACh binding sites at the subunit interfaces and show ligand specificities resembling those of the nicotinic receptor for agonists and antagonists. A subset of ligands, termed the neonicotinoids, exhibit specificity for insect nicotinic receptors and selective toxicity as insecticides. AChBPs are of neither mammalian nor insect origin and exhibit a distinctive pattern of selectivity for the neonicotinoid ligands. We define here the binding orientation and determinants of differential molecular recognition for the neonicotinoids and classical nicotinoids by estimates of kinetic and equilibrium binding parameters and crystallographic analysis. Neonicotinoid complex formation is rapid and accompanied by quenching of the AChBP tryptophan fluorescence. Comparisons of the neonicotinoids imidacloprid and thiacloprid in the binding site from Aplysia californica AChBP at 2.48 and 1.94 A in resolution reveal a single conformation of the bound ligands with four of the five sites occupied in the pentameric crystal structure. The neonicotinoid electronegative pharmacophore is nestled in an inverted direction compared with the nicotinoid cationic functionality at the subunit interfacial binding pocket. Characteristic of several agonists, loop C largely envelops the ligand, positioning aromatic side chains to interact optimally with conjugated and hydrophobic regions of the neonicotinoid. This template defines the association of interacting amino acids and their energetic contributions to the distinctive interactions of neonicotinoids.  相似文献   
19.
Effect of statins on the development of renal dysfunction   总被引:2,自引:0,他引:2  
Hydroxymethylglutaryl coenzyme A reductase inhibitors (statins) decrease serum cholesterol. Dyslipidemia is believed to be associated with the development of renal dysfunction. It was postulated that statins may reduce the development of renal dysfunction. The effect of statin use on the development of renal dysfunction in 197,551 patients (Department of Veterans Affairs, Veterans Integrated Service Network 16 [VISN16] database) was examined. Of these patients, 29.5% (58,332 patients) were statin users and 70.5% (139,219 patients) were not. Development of renal dysfunction was defined as doubling of baseline creatinine or increase in serum creatinine > or =0.5 mg/dl from the first to last measurement with a minimum of 90 days in between. During 3.1 years of follow-up, 3.4% of patients developed renal dysfunction. After adjustment for demographics, diabetes mellitus, smoking, hypertension, and other medications (mainly angiotensin-converting enzyme inhibitors, calcium channel blockers, and aspirin), use of statins decreased the odds of developing renal dysfunction by 13% (odds ratio [OR] 0.87, 95% confidence interval [CI] 0.82 to 0.92, p <0.0001). The beneficial effect of statins appeared to be independent of the decrease in cholesterol. Other variables that affected the development of renal dysfunction were age (OR 1.04, 95% CI 1.03 to 1.04, p <0.0001), diabetes (OR 1.77, 95% CI 1.68 to 1.86, p <0.0001), hypertension (OR 1.11, 95% CI 1.02 to 1.2, p = 0.0153), and smoking (OR 1.12, 95% CI 1.02 to 1.24, p = 0.0244). In conclusion, statin use may retard the development of renal dysfunction. The beneficial effect of statins in preventing the development of renal dysfunction appears to be independent of their lipid-lowering effect.  相似文献   
20.
The 1,3-dipolar cycloaddition reaction between unactivated azides and acetylenes proceeds exceedingly slowly at room temperature. However, considerable rate acceleration is observed when this reaction occurs inside the active center gorge of acetylcholinesterase (AChE) between certain azide and acetylene reactants, attached via methylene chains to specific inhibitor moieties selective for the active center and peripheral site of the enzyme. AChE catalyzes the formation of its own inhibitor in a highly selective fashion: only a single syn1-triazole regioisomer with defined substitution positions and linker distances is generated from a series of reagent combinations. Inhibition measurements revealed this syn1-triazole isomer to be the highest affinity reversible organic inhibitor of AChE with association rate constants near the diffusion limit. The corresponding anti1 isomer, not formed by the enzyme, proved to be a respectable but weaker inhibitor. The crystal structures of the syn1- and anti1-mouse AChE complexes at 2.45- to 2.65-A resolution reveal not only substantial binding contributions from the triazole moieties, but also that binding of the syn1 isomer induces large and unprecedented enzyme conformational changes not observed in the anti1 complex nor predicted from structures of the apoenzyme and complexes with the precursor reactants. Hence, the freeze-frame reaction offers both a strategically original approach for drug discovery and a means for kinetically controlled capture, as a high-affinity complex between the enzyme and its self-created inhibitor, of a highly reactive minor abundance conformer of a fluctuating protein template.  相似文献   
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